关于上标运算符和用指针加偏移量访问的区别

         //analysis the shstrtab offset in the file
    ioffset = shdr[phead->e_shstrndx].sh_offset;
    isize = shdr[phead->e_shstrndx].sh_size;
    
    pshstr = (char*)malloc(sizeof(char)*isize);
    //read the shstrtable from file     
    if( 0 != fseek(p,ioffset,SEEK_SET) )
    {
        printf("move the offset for shstrtab failed!\n");
    }
    iRet = fread(pshstr,isize,1,p);
    if( 1 != iRet )
    {
        printf("read the shstrtab from file failed!\n");
    } 
    printf("The Section of Elf file: %d\n",phead->e_shnum );
    printf("Index    Name    size    offset \n");
    for( i = 1; i< phead->e_shnum ; ++i )
    {
        printf("%d    ", i);
        printf("%s    ",pshstr+shdr[i].sh_name );//使用下标pshstr[shdr[i].sh_name]就会出现段错误
        printf("%d    ",shdr[i].sh_size);
        printf("%d    ",shdr[i].sh_offset);
        printf("\n");    
    }